Methods and systems can prove to an independent verifier that multiple activities registered on decentralized BASE network belong to the same user, without revealing true identity of the user. A selective linkability algorithm provides for linking together activities done under various of user's pseudonyms, without revealing the true user's identity. A reward calculation mechanism calculates a reward based on activities linked using the linking proof. For example, if user can prove that she already successfully completed 10 prior transactions, she might be deemed more valuable to the business making a new offer and hence eligible for a higher reward.

A method for implementing blockchain-based transactions comprises: determining a transaction amount to be remitted from a blockchain account of a remitter into a blockchain account of a receiver, wherein the blockchain account of the remitter records a homomorphic encryption ciphertext of the remitter's balance, the blockchain account of the receiver records a homomorphic encryption ciphertext of the receiver's balance; generating a homomorphic encryption ciphertext of the transaction amount with respect to the remitter and a homomorphic encryption ciphertext of the transaction amount with respect to the receiver; and submitting to the blockchain a transaction for the homomorphic encryption ciphertext of the transaction amount with respect to the remitter to be subtracted from the homomorphic encryption ciphertext of the remitter's balance and for the homomorphic encryption ciphertext of the transaction amount with respect to the receiver to be added to the homomorphic encryption ciphertext of the receiver's balance.

The technology disclosed teaches protecting sensitive data in the cloud via indexable databases. The method includes identifying sensitive fields of metadata for encryption and for hashing. The method also includes hashing at least partial values in the indexable sensitive fields to non-reversible hash values, concatenating the non-reversible hash values with the metadata for the network events, and encrypting the sensitive fields of metadata. Also included is sending the metadata for the network events, with the non-reversible hash values and the encrypted sensitive fields, to a remote database server that does not have a decryption key for the encrypted sensitive fields and that indexes the non-reversible hash values for indexed retrieval against the indexable sensitive fields. The disclosed technology also teaches retrieving sensitive information that is secured at rest: receiving a sensitive field query, hashing the query, querying and receiving network event metadata responsive to the query, and decrypting the metadata.

A method for maintaining user privacy in advertisement networks may include receiving first persona data associated with a first user from at least one publisher system. The first persona data may be generalized to form first generalized persona data. A session key may be generated. The first generalized persona data and the session key may be encrypted with a first public key of an advertisement network system to form a first ciphertext. The first ciphertext and first user identity data may be communicated to a mediator system. The first user identity data may be associated with the first user's identity. A first encrypted targeted advertisement may be received based on the first generalized persona data from the advertisement network system via the mediator system. The first encrypted targeted advertisement may be decrypted with the session key to form a first targeted advertisement. A system and computer program product are also disclosed.

Systems, methods, and software are disclosed herein to generate a customized view of a blockchain transaction. A blockchain of block entries requested by a plurality of users from user devices is maintained in a distributed network of nodes. The block entries each comprise a plurality of data portions that are each associated with an access level. A request to view one or more data portions of a block entry is received which includes an access code associated with at least one access level. The access code in the request is evaluated with the blockchain of block entries to identify one or more data portions associated with the access level. A customized view of the block entry is generated which includes the one or more data portions associated with the access level.

Various embodiments of the present technology provide a distributed overwatch system that allows transactions with government-grade privacy and security. The security and privacy can be achieved by a combination of distributed trusted proxies, to which anonymous users connect with the overwatch of a variety of network security engines. The structured ecosystem provides mechanism for the blockchain to be monitored by an overwatch capability combining big data analytics, intelligent learning, and comprehensive vulnerability assessment to ensure any risks introduced by vulnerabilities are effectively mitigated. The system may include multiple proxy servers geographically distributed around the world. Each proxy can be associated with local network security engines to probe and analyze network traffic. Each proxy can mask sensitive data (e.g., personally identifiable information) within the transaction before it is stored. Various embodiments can interface with most blockchain or distributed ledger technologies that support multi-signature transactions and/or smart contracts.

A search device (60) determines whether or not an auxiliary tag AT corresponding to an auxiliary query AQ obtained by conversion of a keyword exists, among auxiliary tags AT stored in an auxiliary tag storage unit (632) and obtained by conversion of a search word. When it is determined that the auxiliary tag AT corresponding to the auxiliary query AQ exists, the search device (60) specifies an encryption tag ET corresponding to a search query SQ being set with attribute information x indicating an attribute of a user, and the keyword, among encryption tags ET stored in an encryption tag storage unit (633) and being set with an access condition v indicating an accessible attribute, and the search word.

A terminal, a server, and a system for authenticating biometric information and a biometric information authentication method are provided. A method, performed by a terminal, of registering biometric information includes: transmitting a registration request and biometric capability information of the terminal to a server; receiving biometric capability information of the server from the server; acquiring a user's biometric information based on the biometric capability information of the server; acquiring a pseudonymous identifier (PI) and auxiliary data (AD) based on the user's biometric information; and transmitting the PI and the AD to the server.

Privacy management techniques for communication systems are provided. In one or more methods, one or more cryptographic key pairs are provisioned in a home network of a communication system for utilization by subscribers of the home network to conceal subscriber identifiers provided to access points in the communication system. The cryptographic key pairs are managed utilizing an element or function in the home network of the communication system. In one or more other methods, one or more public keys associated with one or more cryptographic key pairs are stored in user equipment, the cryptographic key pairs being provisioned by a home network of a communication system for use by subscribers of the home network to conceal subscriber identifiers provided to access points in the communication network. An element or function of the home network of the communication system is interfaced for management of the public keys stored in the user equipment.

Systems, computer-readable media, and methods for improving both data privacy/anonymity and data value, wherein data related to a data subject can be used and stored, e.g., in a distributed ledger data structure, such as a blockchain, while minimizing re-identification risk by unauthorized parties and enabling data, including quasi-identifiers, related to the data subject to be disclosed to any authorized party by granting access only to the data relevant to that authorized party's purpose, time period, place and/or other criterion via the obfuscation of specific data values, e.g., pursuant to the European Union's General Data Protection Regulation (GDPR) or other similar regulatory schemes. The techniques described herein maintain this level of privacy/anonymity while still satisfying the immutability, auditability, and verification mandated by blockchain and other distributed ledger technologies (DLTs) for the decentralized storage of transactional data. Such systems, media, and methods may be implemented on both classical and quantum computing devices.